Guest freud Posted July 19, 2004 Posted July 19, 2004 I get a reoccuring vapor lock problem, I basically overheat at stoplights, in the sun, when the wind blows, etc. I believe it is the reduculous place that Guxxi placed the fuel pump on my bike. Has anyone dealt with with this and found a way to keep it from happening? I know that on later models the pump is relocated inside the tank but $1500 for an updated tank is a little steep. The heat sheilding I have over the pump is not enough to keep it from happening and, I suspect the altitude (The Mile High City, Denver) is not helping the problem. I really wish I had a petcock and carbs again, like on any of my old Le Manns'... boo hoo freud
TX REDNECK (R.I.P.) Posted July 19, 2004 Posted July 19, 2004 Grasshopper, let your quest begin here in the FAQ section http://www.v11lemans.com/forums/index.php?showtopic=462
callison Posted July 19, 2004 Posted July 19, 2004 Mine did that exactly once when I had about 21,000 miles on it. That didn't make sense, but I had taken the tank off the day before, so I went looking for the culprit. In this specific instance, the tank had been converted to a standard petcock which requires re-routing the fuel line. There was quite a bit of strain tangent to the spigot departure angle, so when the fuel line itself got enough heat to soften up a tad - it kinked. Re-routing the fuel line cured that problem. This recurring vapor lock issue always seems to be attributed to the fuel pump and its location. MG has moved the pump to several locations, finally immersing it in the tank. Al has tried a number of novel plumbing approaches as have several other people. There doesn't seem to be a total consistency in the results. Perhaps the problem is not the pump, but the electric petcock. The solenoid actuator on there could be failing after its internally generated heat plus the heat from the engine is more than it can accommodate. Of course, if this is the case, and all of MG's maneuvering the pump location didn't help, when the pump was moved to the tank, that particular petcock part was removed as part of the design, and it would have cured the problem. In the most expensive way - by completely redesigning the tank and its associated parts. I make no claim that this is the actual problem, only that it is a possible alternative culprit.
al_roethlisberger Posted July 19, 2004 Posted July 19, 2004 FYI: The electric petcock disappeared and reverted to a manual type in 2002 There's not even a hookup on the harness in 2002 for the electric petcock of the 00/01 models as far as I can tell. But to the point here, based on his description, I don't think his problem is the electric petcock on his bike.... although this is certainly an area to also check for related problems as his is an 00 and probably does have this little gremlin fitted <_> WRT the vapor lock though, before going the nutso route I've gone moving things all around, etc(which does help though), I would first check to see where the fuel supply line is routed, and if too close to the left cylinder, move it away... or make a new longer line, with heat shielding, to get it as far away from the heat as possible. Most people don't seem to have this problem, and we don't know why some bikes are more susceptible than others. But high heat and altitude certainly don't help. al
docc Posted July 22, 2004 Posted July 22, 2004 certainly some of our bikes are set up leaner ( therefor hotter) than others. Be sure your TPS is in range and the throttle body balance is on. Sometimes the fuel pump ( if it's mounted under the frame like mine) is against the oil line. Simply loosen the bracket and slide it u pand away from the line fitting.
Guest freud Posted July 23, 2004 Posted July 23, 2004 I really appreciate all of the suggestions, this is one of the 65 or so bikes that had the engine AND transmission recall on it... The Gremlins are strong within this one, my son. I just LOVE how they nailed the look (really nailed that one) and overall ride of this bike and screwed up the fuel system <insert="frowny face"> at least there's you guys to help.... I feel like I'm about to start another horribly painful Guzzi modification, like the time I rewired my T3..... or the time I changed out the switchgears on my 87 Lemans to Honda parts.... Or..... Or.... I feel like I'm in a really complex high-maintance relationship with an entire family of progressivly more genius, and beautiful but, entirely screwed up children. Based on suggestions by doc and callison: ???Does anyone think that this problem might clear up a little with individual fillament K and Ns, rerouting the lines, removing the emmisions garbage, Changing the pipes to a more direct flow (FBF, Mistral, whatever), but more importantly getting it dyno run and set with a PC3 to better deal with the altitude??? it would certainly run less lean then... Any thoughts? Anybody?? Thank you for you help, Freud
jrt Posted July 23, 2004 Posted July 23, 2004 I feel like I'm in a really complex high-maintance relationship with an entire family of progressivly more genius, and beautiful but, entirely screwed up children. Nicely put. That's probably more accurate than we care to admit, although you have to wonder- genius or idiot-savante ? The things that will help are those that allow the motor to run cooler (richen it up a bit), allow more airflow through the center of the bike, and moving the fuel system away from heat. A PCIII will get you the first- it may be just the ticket for altitude (I have no experience here). To get the second, you could switch to K&N's, remove the airbox, and you get vast tracts of real estate under the tank. From what I've read, the primary thing to look for, however, is the routing of the fuel hose. Make sure it is as far away from the cylinders as possible. Removing the evaporative cannisters will also give you a little more airflow under there, but won't do anything about the state of tune. And...they are there for environmental protection, so at least consider that before ripping them out. J
Guest Fonzarelli Posted July 23, 2004 Posted July 23, 2004 Have you checked or replaced your fuel filter? Sometimes it is the simplest of things. Also, depending on the condition of things, there might be some sort of air brake causing low fuel pressure.
Guest John T Posted July 24, 2004 Posted July 24, 2004 FYI: The electric petcock disappeared and reverted to a manual type in 2002 Ahh, I like to zing Al when I can. 2001 Rosso Mandello came with manual petcock. Not sure about the other variants of the '01 model year.
Guest davidb Posted July 24, 2004 Posted July 24, 2004 the evaporative canisters Can cause a lean mix. they are plumbed to the throttle bodies and use a built in check valve system that has been known to fail. Trash it.
Guest freud Posted July 30, 2004 Posted July 30, 2004 Alright fellas, based on the numerous sugestions I am doing the following things: 1. Rerouting the damn fuel lines, if this dosen't make a signifigant differance, I am buying the aircraft fuel line (asbestos coated stuff as suggested). If that dosen't work I am driving it off a cliff (of which there are many in Colorado) Harold and Maude style... 2. Replacing the fuel filter with a smaller plastic one. 3. Removing the tip-over valve. 4. Changing the system to K & N Pods, they will be here tuesday. Halleugha! (SP?) 5. Buying a PCIII, which should be here in a week or so. And, can I just say that somehow the dyno fee OUGHT to be included! 6. Removing every single piece of emmision equipment. I'm sorry jrt, but they took my two stroke away, this is the best I can do. 7. Changing the "Moto Guzzi" decal to a "Moto Guzzi V11 Forum" as it seems morre appropriate... freud
docc Posted July 30, 2004 Posted July 30, 2004 7. Changing the "Moto Guzzi" decal to a "Moto Guzzi V11 Forum" as it seems morre appropriate... The fuel filter has a pretty high specification for flow, filtration and surface area. The best one we've found is a lazer welded stainless steel unit spec'd for the Isuzu Trooper 9 and it is a little smaller than the Weber unit). Wrap it in some insulation if the heat is a concern. Your filter is under the frame or on top?
jrt Posted July 30, 2004 Posted July 30, 2004 1. Rerouting the damn fuel lines, if this dosen't make a signifigant differance, I am buying the aircraft fuel line (asbestos coated stuff as suggested). If that dosen't work I am driving it off a cliff (of which there are many in Colorado) Harold and Maude style... Be sure and take pictures! One other thing you might try cycling the kill switch two or three times. That will push some fuel around and maybe help out. J
al_roethlisberger Posted July 30, 2004 Posted July 30, 2004 Yes, as mentioned.... *do not* change the filter to any old plastic filter(or glass, or even a metal unit not specific for this application), such as those intended for a non-pressurized fuel system. ~45psi and a hot plastic filter would not be a good combination The stock filter, being on top of the spine(generally ) probably isn't the main problem with the VL, and I simply put some heat shielding around it with acceptable results. Here is the "evolution" of my efforts: Relocating Fuel Pump Thread Until I finally: Retrofitted a 2003 spec tank.... And while we are at it: Wasted Fuel Thread 2003 Tank Capacity al
Guest freud Posted July 31, 2004 Posted July 31, 2004 Thank you again fellas for the help on the filter, the bike in flames seems appropriate under the circumstances, although I have discovered twice while driving that the low pressure hose is off my bike and leaking profusely, not causing an explosion, one of those times I was smoking, no really I was. Anyhoo... I will try to fit the trooper filter, and mine is on top, as I belive it should be. Although if you have anything I should know before I remove the airbox completely and otherwise reroute EVERYTHING please feel free to make your observations and opinions known. I called Harpers, and the manual petcock is on backorder...crap. (and I think I am going to have tho get Ferracci cans and X over, because they are the only thing available it seems) But I think everything will be better after the extra space is made and I can do some retubing and such I think I may just try to reposition and shorten things first. I am putting quick disconnects on all of my fuel line, they are on order now and should be here next week... And for now, new tires. I am about to search your database for the best available.. the millions of uses for websites about quirky bikes. Funny, I just corrected a typo, I typed "bikers" rather than "bikes". maybe that was subconcious... I probably shouldn't think too deeply about this as my name really is J Freud Reia. Hmmm... back to working graveyards... thanks again. Freud :!: I really need to work on my profile after my broadband is up.
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